USING THE VM/370 SPOOL FILE A user should let the VM/370 spool file system handle printer or punch
output that does not have to be printed or punched. For example: When using the alternating route print output to the virtual card
reader by using this CP SPOOL command: tcp spool printer to *
After issuing this command, a user can subsequently load the systea and create a CMS file from the data in the virtual reader (by using the CMS READCARD command). Then, by using the CMS editor, the user can scan
the contents of this data at his terminal.
Preparing Jobs for an OS/VS Virtual Machine Prepare and submit a job stream to an OS/VS virtual machine in one of
two ways: • Place a deck of real punched cards that contain the appropriate job
control, Frogram and data in the real card reader. Place a CP ID
statement at the beginning of this job stream deck to indicate the OS/VS userid; for example:
ID OSVS or -- USERID OSVS Either statement is a valid ID statement for directing the input that
follows to the OSVS user's virtual reader (the reader with the
lowest virtual device address). • Use the CMS system to create a CMS file containing images of what
would normally be submitted through a card reader on a real System/310. Enter the CP SPOOL command to cause subsequent punched
output to be directed to the virtual card reader of the OS/VS machine. Enter the CMS PUNCH command to generate the virtual card
deck:
cp spool punch to osvs
punch vsjob27 jcl (noheader
The NOHEADER option of the PUNCH command suppresses punching a READ control card at the beginning of the deck.
A job stream spooled to OS/VS by either of these methods remains in the
card reader of the OS/VS virtual machine until the user starts an as/vs
reader,. When spooling jobs to a virtual machine, clear
remain in the virtual punch from previous jobs by commands: any data that may
issuing these CP cp spool punch nocont
cp close punch purge
These commands ensure that the virtual punch is purged
reader files. The first command is required if the
originally spooled with the CONT operand.
128 IBM operating Systems in a Virtual Machine
of any existing
punch had been

JaB ENTRY AND OUTPUT RETRIEVAL When running QS/VS in a'virtual machine, a primary consideration is job
entry and Several techniques can be used for these
functions: • Use the OS/VS virtual machine in batch mode where it operates as OS/VS in native mode. It reads in job streams through a dedicated
card reader and prints output generated by the virtual machine on a
dedicated printer. • A single directory entry (userid) can contain a configuration
sufficient for running both and OS/VS (the alternating
technique). Load CMS to create and edit as/vs job streams and to
check the as/vs output. Load as/vs to run the as/vs job streams. • Use two different userids to keep two virtual machines running.
(This is the optimum environment.) Use one userid for the OS/VS machine while using the other for a CftS machine to create job streams
and inspect output. By using the CP DISCONN command, users can run
both virtual machines from the same terminal. Thus, both machines
are running concurrently, but a user communicates with only one at a
time. If two· terminals are available, each system can run
independently of the other.
Loading OS/VS At legan, use the userid for running as/vs. It lIay be a user's own userid when running alternating or concurrent systems. It may be a special userid that an installation has set aside exclusively for the OS/VS machine.
logon osvs
Because extended control (EC) mode is required to operate CS/VS, the
directory entry should contain the ECMaDE specification on the OPTICN control statement. If it is not included, enter this CP command to
enatle extended control mode simulation:
set eCllode on !Qte: To run OS/PCP and OS/MFT, a user does not need the ECMODE option.
To run OS/MVT, a user does not need the ECMODE option unless running the
generalized trace facility (GTF) under OS/MVT. However, OS/PCP, and OS/MVT normally required the REALTIMER option.
At this point, between logging on and loading the operating system, a
user may find it desirable or necessary to alter the virtual machine's
storage size. For exam FIe: If the directory entry specifies 1 megabyte
of storage and a user needs 2 megabytes for this particular terminal
session, issue the CP DEFINE command:
define storage as 2m Virtual machine storage can be redefined up to the limit set in the USER central statement of the directory entry. Once the IPL volume is made available, enter this command to load
as/vs:
ipl 250 Section 4. as/vs in a Virtual Machine 129